encode the uploaded file's name in the default external encoding - Closes #869

actionpack/lib/action_dispatch/http/upload.rb

@@ -4,7 +4,7 @@ class UploadedFile
       attr_accessor :original_filename, :content_type, :tempfile, :headers
 
       def initialize(hash)
-        @original_filename = hash[:filename]
+        @original_filename = encode_filename(hash[:filename])
         @content_type      = hash[:type]
         @headers           = hash[:head]
         @tempfile          = hash[:tempfile]
@@ -30,6 +30,17 @@ def rewind
       def size
         @tempfile.size
       end
+      
+      private
+      def encode_filename(filename)
+        # Encode the filename in the default_external encoding, unless it is nil or we're in 1.8
+        if "ruby".encoding_aware? && filename
+          encoding = Encoding.default_external
+          filename.force_encoding(encoding)
+        else
+          filename
+        end
+      end
     end
 
     module Upload

actionpack/test/dispatch/uploaded_file_test.rb

@@ -12,6 +12,18 @@ def test_original_filename
       uf = Http::UploadedFile.new(:filename => 'foo', :tempfile => Object.new)
       assert_equal 'foo', uf.original_filename
     end
+    
+    if "ruby".encoding_aware?
+      def test_filename_should_be_in_default_encoding
+        Encoding.default_external = "UTF-16LE"
+        uf = Http::UploadedFile.new(:filename => 'foo', :tempfile => Object.new)
+        assert "UTF-16LE", uf.original_filename.encoding.to_s
+        
+        Encoding.default_external = "UTF-8"
+        uf = Http::UploadedFile.new(:filename => 'foo', :tempfile => Object.new)
+        assert "UTF-8", uf.original_filename.encoding.to_s
+      end
+    end
 
     def test_content_type
       uf = Http::UploadedFile.new(:type => 'foo', :tempfile => Object.new)